In this experimental work the effect of agglomeration in the starting powder of alumina feedstocks was analysed. Two pre-treated powders: one pre-coated with SA and a spray dried powder were used for comparison with the as received powder. Alumina feedstock was prepared with 58 vol. %. of powder and a binder system based on high density polyethylene (HDPE), paraffin wax (PW) and stearic acid (SA). The mixing process was optimized by means of mixing torque measurement. Rheological behaviour of three feedstocks was analysed using capillary rheometry. All the feedstocks exhibited a pseudoplastic behaviour with n < 1 according to the Herschel-Buckley model. Feedstocks with spray dried powder showed the lowest viscosity and this could allow to incorporate higher ceramic loading decreasing shrinkage and increasing densities of sintered parts.